A Microbiologist Would Like to Use a Noncompetent Genus of Streptococcal

question 16

Multiple Choice

A microbiologist would like to use a noncompetent genus of streptococcal bacteria,Enterococcus faecalis,as a cloning host to express genes from Streptococcus pneumoniae,which is naturally competent.Is this possible?

• A)Yes; electroporation or chemical transformation can be used to make Enterococcus competent,and then genes from Streptococcus can be introduced via a cloning vector.
• B)Yes; electroporation or chemical transformation can be used to make non-competent Streptococcus mutants,from which genes can be inserted into a cloning vector and introduced into Enterococcus.
• C)No; competence factor is an essential protein that enables the uptake of foreign DNA,therefore a cloning host such as Enterococcus that lacks competence factor protein is unable to be transformed by electroporation or chemical transformation.
• D)Yes; since the cloning host and the DNA to be introduced are both from bacteria that are streptococci,natural competence in this case is not necessary as long as the appropriate vector is used.

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Definitions:

Discounted Payback

A capital budgeting technique that calculates the amount of time needed to recoup an investment based on the present value of its cash flows, accounting for the time value of money.

Variable Cost

Overheads that see variation directly aligned with output quantities.

Operating Leverage

The degree to which a company can increase its profits by increasing sales, highlighting the fixed versus variable costs structure.

Base-Case Scenario

In financial modeling and decision making, it refers to the standard set of assumptions used as a baseline for projecting the financial performance or outcome of a project.